Clinical Research Directory

Key Inclusion Criteria: * Age 1 to 17 years * Clinical diagnosis of RRP with histologically confirmed papilloma * Laryngotracheal papillomas accessible for endoscopic debulking * At least 3 lifetime debulking procedures (the Day -1 procedure counts) * Active RRP, shown by at least 1 clinically indicated debulking procedure within the 12 months before treatment, including the Day -1 procedure. For participants who received systemic bevacizumab, the qualifying procedure must show recurrence of active disease after bevacizumab was stopped; if the Day -1 procedure is used, it must be clinically indicated for recurrent disease. * Willing to undergo endoscopic evaluation, operative interventions, and biopsies per protocol Key Exclusion Criteria: * Any condition, therapy, or lab abnormality that would increase participation risk, impair receipt of protocol therapy, or confound interpretation of results, per the Investigator * Systemic corticosteroids (\>2 mg/kg/day or \>10 mg/day prednisone equivalent) or other immunosuppressants within 14 days of dosing (inhaled, topical, intranasal, intra-ocular, and adrenal replacement doses permitted) * Any systemic or intralesional RRP treatment, including bevacizumab and investigational agents, within 30 days or 3 half-lives of the prior treatment, whichever is longer * Any vaccine within 30 days before the first dose * Persisting Grade \>1 toxicity from prior therapy (alopecia and Grade ≤2 events not posing a safety risk are acceptable) * History of heparin-induced thrombocytopenia (HIT) or vaccine-induced immune thrombotic thrombocytopenia (VITT)